This invention relates to a highly combustible fuel and a process for producing such fuel; more especially the invention concerns such a fuel for motor driven vehicles such as automobiles, trucks and boats which traditionally employ gasoline as fuel, as well as aircraft fuel and furnace applications, and which fuel exhibits low exhaust pollutant levels and high efficiency.
Motor driven vehicles such as automobiles and aircraft are fueled by a mixture of gasoline and air. Automobiles employ a carburetor or a fuel injection which produces an explosive mixture of gasoline and air by spraying the gasoline into air. The mixture may be swirled through an intake manifold and delivered to the engine cylinders of an internal combustion engine; or the gasoline may be injected or inducted directly into the cylinders and the air may be delivered separately through the intake manifold. Whichever way the mixture is formed it is crude and unstable and if not combusted immediately droplets of liquid gasoline fall from the mixture.
Aromatic hydrocarbons are included in gasoline to slow the combustion process and reduce knocking in the cylinders.
Such mixtures also result in significant levels of pollutants when combusted.
This invention seeks to provide a highly combustible fuel for motor driven vehicles, more efficient and exhibiting lower levels of exhaust pollutants than conventional mixtures of gasoline and air.
In accordance with one aspect of the invention there is provided a process of producing a combustible fuel comprising exposing a gaseous hydrocarbon fuel to an electrical field or plasma or to ultraviolet radiation, microwave radiation or laser to produce a fuel of improved combustibility as compared with said hydrocarbon fuel.
More especially the exposure is at an elevated temperature and charged particles are derived from the gaseous hydrocarbon fuel, the charged particles being fed to the engine cylinder. The charged particles may bear a negative charge or a positive charge but negatively charged particles are preferred.
In accordance with another aspect of the invention there is provided a combustible fuel produced by the aforementioned process of the invention.
In accordance with a specific embodiment of the invention there is provided a process of producing a combustible fuel comprising: a) introducing a gaseous, oxygeneous fluid into an atmosphere of gaseous hydrocarbon fuel maintained under vacuum, and b) establishing an electrical potential difference across said atmosphere or irradiating said atmosphere with ultraviolet radiation, microwave radiation or laser to produce a combustible fuel of said oxygeneous fluid bound to said gaseous hydrocarbon fuel.
In accordance with another embodiment of the invention there is provided a combustible fuel which is a homogeneous composition produced by a) introducing a gaseous, oxygeneous fluid into an atmosphere of gaseous hydrocarbon fuel maintained under vacuum, and b) establishing an electrical ionization potential difference across said atmosphere or irradiating said atmosphere with ultraviolet radiation, microwave radiation or laser to produce a combustible fuel of said oxygeneous fluid bound to said gaseous hydrocarbon fuel.
i) General Process
In the process of the invention a gaseous hydrocarbon fuel is exposed to an electrical field or plasma, more especially an electrical ionization potential difference, or to ultraviolet radiation, microwave radiation or laser.
The exposure may be carried out in the presence of a gaseous carrier fluid, for example, an oxygeneous fluid such as oxygen and/or air, or a mixture of oxygen and/or air and steam or gaseous water vapor. Other gaseous carrier fluids include nitrogen and the inert gases, for example, argon and helium.
While not wishing to be bound by any particular theory as to the mechanism of combustible fuel production, it is postulated in one theory that the electrical ionization potential difference, or the radiation activates the gaseous hydrocarbon fuel to a high energy state, more especially the hydrocarbon molecules or ions of the fuel are thought to be electronically excited to a state in which they are more reactive or more susceptible to combustion than the hydrocarbon fuel in the non-excited state.
Another theory is that the process generates an extremely finely divided aerosol having a particle size far smaller than that achieved with a normal carburetor or fuel injector equipped system. Under the conditions of formation, the droplet particles are initially formed in a strongly electrically-charged condition. This is a metastable condition, leading immediately to the disruption of the highly charged droplets by internal coulombic repulsion and the formation of much more finely divided droplets each of which carries a portion of the charge initially held by the original droplet. These second generation droplets may then rapidly and similarly undergo further disruption and dispersion and so on until the fuel-air mixture enters the combustion chambers and is ignited. Mutual electrostatic repulsion between these fuel particles prevents them from coalescing back to larger droplets. Furthermore, the droplets enter the combustion chambers relatively more finely divided than in a normal carburetor or fuel injector equipped system. Since burning of the fuel in the combustion chambers occurs at the fuel particle surface, its rate is therefore dependent upon the surface area. Burning at high engine speeds is incomplete before normally-sized droplets in the normal carburetor or fuel injector equipped systems are ejected as exhaust, and therefore completeness of combustion is compromised if the droplet size is large. On the other hand, an extremely finely divided dispersion provides a huge increase in the surface area for burning and leads to much more complete combustion with the resulting decrease in carbon monoxide and unburnt hydrocarbon emissions which are observed with this invention.
A reactor employed in the invention was modified to incorporate a very fine mesh screen in the out flow stream of the reactor; the screen was insulated from the reactor components but electrically connected to an external detector of electrical current. In operation electrical charging of the screen was detected and it is likely that this results from partial collection and discharging of the charged droplets.
The presence of the charge on the droplets of the aerosol likely enhances the ease with which the fuel dispersion is combusted, especially when the droplets are negatively charged, since the negatively charged droplets would have an increased affinity, for oxygen adduction.
It is also possible, but not confirmed that this excited state or charged droplets of the hydrocarbon molecules or ions may become bound to the gaseous carrier fluid, especially when the carrier fluid is an oxygeneous fluid, such as by forming an adduct between the oxygeneous fluid and the charged droplets.
In order to expose the atmosphere to the ultraviolet or microwave radiation or to laser beam, the chamber housing the gaseous hydrocarbon fuel may include a window transparent to the radiation or laser beam whereby the radiation or beam may be directed to the atmosphere of the gaseous hydrocarbon fuel.
ii) Specific Process
In a particular process within the aforementioned General Process, a gaseous, oxygeneous fluid is introduced into an atmosphere of gaseous hydrocarbon fuel maintained under vacuum.
The gaseous, oxygeneous fluid is suitably oxygen and/or air, or a mixture of oxygen and/or air and steam or gaseous water vapor.
The hydrocarbon fuel is suitably gasoline by which is to be understood the various grades of gasoline motor fuel; hydrocarbon fuel may also be diesel oil, natural gas or propane.
Conveniently the atmosphere of gaseous hydrocarbon fuel is formed by vaporizing a liquid hydrocarbon fuel, for example, gasoline, under vacuum or a slight pressure in a chamber. The use of a vacuum facilitates formation of the gaseous atmosphere from the liquid hydrocarbon fuel. Conveniently the vacuum corresponds to a negative pressure of 3 to 28, preferably 10 to 28 inches of mercury; when the vaporization is carried out at a slight pressure this is suitably 15 to 16 psi and the atmosphere is formed at a temperature, relative to the pressure, of up to but not to exceed the fuel flash point. Test temperature can be increased up to the flash point of hydrocarbon fuel, but not exceeding it or explosion of said fuel can occur, resulting in personal injury to the experimenter.
Suitably the vaporization is carried out at an elevated temperature, which conveniently is 250xc2x0 F. to 450xc2x0 F. (121xc2x0 C. to 232xc2x0 C.), more especially 350xc2x0 F. to 410xc2x0 F. (177xc2x0 C. to 210xc2x0 C.). The pressure extending from vacuum through partial vacuum to a slight positive pressure may be considered to be 0-16 psi.
The gaseous, oxygeneous fluid is conveniently introduced continuously into the hot atmosphere in the chamber, and the formed combustible fuel is continuously withdrawn from the chamber and delivered to the cylinders of an internal combustion engine, preferably within 5 minutes of its formation and more preferably within milliseconds of formation.
The electrical ionization potential established across the atmosphere of the hydrocarbon fuel containing the oxygeneous fluid is suitably 200-8000 volts, more usually 600-5000 volts. This is achieved by a pair of spaced apart electrodes disposed so as to be within the aforementioned atmosphere. The spacing of the electrodes is such that any current flow resulting from the potential difference applied across the electrodes is minimal, typically of the order of 0.2 to 0.8 microamps. An average of 0.5 microamps was measured in the test set-up described herein. It should be noted that electrode area and configuration will affect the current flow. Arcing must not occur between electrodes or against any part of the set-up.
In reactors employed for carrying out the invention, one electrode is disposed within the reactor and the other electrode may be defined by the wall of the reactor.
In one particular embodiment the hydrocarbon fuel is sprayed into a chamber from a spray nozzle and the oxygeneous fluid is introduced separately into the chamber, and a potential difference is established between the spray nozzle and a wall of the chamber particularly so as to produce negatively charged fuel droplets. In this embodiment, the spray nozzle functions as an electrode.
In another embodiment the potential difference is established between an electrode extending into the chamber and a wall of the chamber. The spray nozzle directs the hydrocarbon fuel generally axially of the chamber from the spray nozzle towards a fuel outlet of the chamber.
In one structure in accordance with this latter embodiment the electrode extends axially of the chamber with an inner end in spaced opposed relationship with the spray nozzle such that the gaseous hydrocarbon fuel flows axially of the chamber along and about the electrode towards the fuel outlet.
In another structure in accordance with this latter embodiment the electrode extends inwardly of a wall of the chamber and substantially normal to the axial flow of gaseous hydrocarbon fuel from the spray nozzle to the fuel outlet.
In the preferred embodiment in which air is employed as the gaseous, oxygeneous fluid, the air and the gaseous hydrocarbon fuel are suitably employed in a volume ratio of air to gaseous hydrocarbon fuel of 10 to 30:1, preferably 12 to 17:1.
The combustible fuel may be fed directly to the cylinders of an internal combustion engine, no carburetor, choke or injection system is employed. A condensate of the combustible fuel may also be formed, by subjecting the fuel to condensing conditions such as by cooling.
The combustible fuel in gaseous form does not require long term stability as it is normally formed as required and is burned continuously as it is produced, usually within a few milliseconds. The gaseous combustible fuel reverts to a liquid after about 10 minutes.
Formation of the combustible fuel can be observed as a cloud which is a whitish, silvery grey in color, while the gaseous gasoline is colourless. When delivered through a conduit the combustible fluid has been observed to retain the configuration of the bore of the conduit as it emerges from an end of the conduit and to retain this configuration as the fuel advances from the conduit, and then expand to a cloud. In one case when a vacuum was applied to draw the cloud back into the conduit, the cloud shrank to the configuration that it had, when it first emerged from the conduit and the last of it was then drawn into the conduit.
In the embodiment in which the fluid comprises air and steam and the hydrocarbon fuel is gasoline, condensation of the combustible fuel does not result in separation of water and gasoline, as would be expected in the case of a mere mixture. The combustible fuel in condensed form is homogeneous and stable. This combustible fuel is, of course, formed without emulsifiers, surfactants, catalysts or other additives. The steam derived liquid fuel condensate is relatively stable for several days and a test tube sample absorbed two more drops of water into solution readily without any evidence of separation. A third droplet of water was rejected from absorption into the solution and fell directly to the bottom of the test tube. This response being the same as adding a droplet of water directly to gasoline or oil.
In the case where the fluid is air and the gaseous hydrocarbon fuel is gasoline, the formation of the combustible fuel is visible, the cloud of combustible fuel formed about the electrodes being different from the surrounding atmosphere.
iii) Fuel
The gaseous fuel produced in accordance with the invention may be employed directly as produced or a condensate of the gaseous fuel may be produced, which liquid condensate may be employed as a substrate for conventional fuels such as gasoline.
The liquid condensate produced from the combustible fuel developed when the oxygeneous fluid is air or oxygen differs from that produced when the oxygeneous fluid comprises air or oxygen together with steam or water vapor. These two classes of condensate differ both in composition and combustion characteristics.
In accordance with the invention condensates of these two classes may be blended together to provide desired characteristics for particular applications, for example, for automobiles or jet engines or furnaces or boilers.
Furthermore, these condensates, alone or in admixture, may be blended with conventional fuels, for example, gasoline, to provide a blend of desired characteristics. For example, such a blend with conventional gasoline may produce a fuel in which the pollution generated during combustion is reduced in an amount proportionate to the content of the new condensate or condensates in the blend, as compared with that produced by the gasoline alone.